Modification of a dead-bolt relocking device for combination locks



Feb. 12, 1.963 J. c. FITCHETT 3,077,099

MODIFICATION OF A DEAD-BOLT RELOCKING DEVICE FOR COMBINATION LOCKS FiledOct. 12, 1956 2 Sheets-Sheet 1 W 4 2 J5 15 FE .1.

IN V EN TOR.

MURNEYJ' Z0 18 JameJC FZZcfieZi Feb. 12, 1963 J. c. FITCHETT 3,077,099

MODIFICATION OF A DEAD-BOLT RELOCKING DEVICE FOR COMBINATION LOCKS 2Sheets-sheaf. 2

Filed Oct. 12, 1956 Unite States Patent Ofiice 3,077,099 Patented Feb.12, 1963 3,077,099 MODIFICATIUN 6B A DEAD-BOLT RELOCKING DEVICE FURCOMBINATION LOCKS James C. Fitchett, McLean, Va.

(Rte. 1, Lovettsville, Va.)

'Filed Oct. 12, 1956, Ser. No. 615,724 4 Qlaims. (Cl. 70-15) (Grantedunder 'Iitle 35, US. Code (1952), sec. 266) The invention describedherein may be manufactured and used by or for the Government forgovernmental purposes without the payment of any royalty thereon.

This invention relates to locking mechanisms and more particularly to animprovement in combination locks which will lock the dead-bolt in closedposition when an attempt is made to open the lock by tampering with themechanism.

Standard type combination locks include a tumbler mechanism carried on atumbler post which may be turned by a dial located on the front wall ofthe lock box housing the lock mechanism. A bolt extends through one wallof the lock box and is connected to the tumbler mechanism by a lever fornormal operation of the lock. To prevent unauthorized opening of thelock by drilling, punching, or similar methods, present safeguards oncombination tumbler type locks include a locking pin activated by aspring which forces the locking pin into an aperture in the bolt to lockthe bolt in the extended position when an attempt is made to force thelock. The locking pin is normally held out of the locked position by oneend of a lever arm which extends over the back of the tumblers so thatif the tumblers are forced to the rear, as in the punch method offorcing the lock, the lever arm pivots and releases the lock pin.

The present invention is an improvement in the actuating mechanism forthe locking pins engaging the deadbolt and involves the use of a tumblercup, surrounding the tumbler mechanism, a mechanical linkage includingan additional lever arm and rearranging the additional lever arm to beactivated by the forceful molesting of the tumbler cup releasing thespring activated locking pins to engage apertures in the dead-bolt andretain it in the extended position.

It is a principal object of the invention to provide an improvedautomatic operating mechanism for combination locks which will lock thedead-bolt in extended position when an attempt is made to force themechanism the lock.

It is a further object of the present invention to provide an improvedautomatic operating mechanism for combination locks including abalanced, floating enclosure for the lock mechanism which effects arelease of the locking means engaging the dead-bolt to retain it inextended locked position when an attempt is made to force the mechanismof the lock.

A further object of the present invention is to provide a dead-boltlocking mechanism for combination tumbler type locks which will beactuated before any damage is sustained by the normal operating lockmechanism when an attempt is made to force the lock to open.

A further object of the present invention is to provide a constructionfor actuating a dead-bolt locking mechanism which will prevent forcefulopening of the lock even though the normal lock operating mechanism maybe damaged by drilling, punching, or similar methods of forcingcombination locks of the tumbler type.

These and other objects will be evident from the following descriptionwherein- FIG. 1 is a rear view of one form of tumbler type combinationlock embodying the improvements of the instant invention;

FIG. 2 is a vertical sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is a horizontal sectional view through the operating mechanismtaken on the line 3-3 of FIG. 1 with the lock in an upright positionshowing the preset position of the lever arms prior to release of thedeadbolt locking pins;

FIG. 4 is a view of a portion of the operating mechanism as in FIG. 3showing the position of the lever arms upon release of the dead-boltlocking pins;

FIG. 5 is a vertical sectional view taken on the line 5-5 of FIG. 1;

FIG. 6 is a rear view of a tumbler type combination lock including amodified form of the improvements of the instant invention;

FIG. 7 is a horizontal sectional view through the operating mechanismtaken on the line 7-7 of FIG. 6 with the lock in an upright positionshowing the preset position of another form of lever arm prior torelease of the dead-bolt locking pins;

FIG. 8 is a vertical sectional view taken on the line 8-8 of FIG. 6showing the preset position of the lever arms prior to release of thedead-bolt locking pins;

FIG. 9 is a view similar to that shown in FIG. 8 but with the lockingpins in engagement with the dead-bolt after release by the lever arms;

FIG. 10 is a perspective view of the operating mechanism of the modifiedform of the invention as in FIG. 6 showing the relation of the elementscontrolling the operation of the dead-bolt locking pins; and

FIG. 11 is a view taken on the line 9-9 of FIG. 6.

Reference is now made to FIG. 1 showing one form of the invention. Alock box 1 houses the lock operating mechanism including the tumblerstructure shown generally by 2, bolt 3 and lever 4 which overlays therearmost tumbler. As is well known, upon rotation of the dial 6, whichin turn rotates the spindle and tumbler mechanism 2 carried on tumblerpost 8 in accordance With the preset combination of the tumblers, thelever arm 4 coacts with th tumbler structure 2 to move the bolt 3 to theopen and closed position. This portion of the combination lock mechanismis conventional structure well known to those skilled in the art andforms no part of the instant invention. The improvement of the instantinvention includes a floating tumbler cup or shield 9 located within thelock box 1 surrounding the tumbler mechanism 2 and between the free endsof the lever arms 11. The open face of the cup 9 is toward the rear ofthe lock box 1. The bottom of the cup 9 has a hole 12 sutficiently largeto permit the cup 9 to be fitted over tumbler post 8 and collar 13 whichare secured to the inside of box 1. Collar 13 is thicker than the cup 9.This construction enables the tumblers to ride on the collar 13 withoutcoming in contact with the bottom of the cup 9 and consequently notrestricting the freedom of movement of the cup 9, which is essential inorder that the lever arms 11 may release the lockaormso ing pins 14 forengagement with the bolt 3 when an attempt is made to force the lock, aswill be described in more detail hereinafter. The outside surface of thecup 9, at points nearest the side walls of the lock box 1, is providedwith diametrically opposed ribs 15. The ribs 15 project into guides 16secured or formed on th inside walls of the lock box 1 to hold the cup 9in position. The lugs 19 on the cup 9, as shown in F168. 3 and 4,operate the lever arms 11 when the cup 9 is displaced. A flange 17 issecured to an abutment plate 18 which in turn is secured to the innerwall of the cup 9 in a position to act as a stop for the lever 4 duringoperation of the lock mechanism. A flange 21 carried by the abutmentplate 18 projects :over the rearmost tumbler so that when the tumblermechanism is forced to the rear, as when the lock is forced by punchingthe tumbler mechanism 2, the cup 9 will actuate the lever arms 11 torelease the locking pins 14 for engagement with the bolt 3 and maintainit in an extended position. Cup 9 is held in a balanced neutral or safeposition by springs 19 carried on the reduced portions 21 of the shaft22, which is mounted transversely at One end of lock box 1 adjacent thecup 9. An extending arm or lever 23 of each spring 19 engages the rim ofcup 9 to hold the cup in the neutral or safe position. The other end ofthe springs 19 bears against the wall of the lock box 1. The tension inthe springs 19 is sufficient to hold the cup 9 in the safe positionagainst the pressure exerted by the closing or slamming of the safedrawer, but not so strong as to withstand pressure that would be exertedon the cup 9 if an attempt were made to force the lock open such as bypunching or drilling. It is understood that othermeans of mounting thesprings 19 for holding the cup 9 in a safe position and other forms ofsprings may be used without departing from the scope of the invention.

The lever arms 11 are individually supported for free rotation by bolts24 or equivalent means, such as studs, passing through the side walls ofthe lock box 1 and pads 25. The pads 25 are secured to the side walls ofthe lock box 1 by bolts 26 or other convenient means such as by rivetsor welding and serve to mount the locking pins 14 within the lock box 1in a position to engage the bolt 3 and maintain it in an extendedposition. Springs 27 surround the locking pins 14 and are maintained inposition by locking rings 28 retained in circumferential grooves in thelocking pins 14. The locking rings 28 are located a sufficient distanceback from the inner bolt engaging end of each locking pin 14 to permitthe arcuate ends 29 of the lever arms 11 to engage the locking pins 14and seat against the locking rings 28. Looking pins 14 which are urgedinwardly by the springs 27 are thus retained in a present or lockedcondition by lever arms 11. The bolt 3 rides in a slide 31. Theupstanding sides of the slide 31 are provided with apertures 32 whichare in registry with recesses 33 in the sides of the bolt when the bolt3 is in the fully extended position.

' A sleeve 34 is secured to the upper surface of the bolt 3 in anyconvenient manner adjacent the inner end thereof and serves as a supportfor the lever 4. A spring 35 which surrounds the sleeve 34, has one endanchored in the bolt 3 as at 36 and the other end extended to form anarm 37 in engagement with the lever d to urge it into engagement withthe tumbler mechanism 2. With the bolt 3 in the locked or extendedposition, if an attempt is made to force the lock open by punching thetumblers inwardly, it is apparent that the rearmost tumbler will contactthe flange 2d and force it inwardly. This action will move the cup 9inwardly against the action of springs 19 from its normally safeposition and in so doing will cause the lugs on the cup 9 to contact thelever arms 11 and rotate them from the position shown in FIG. 3 to thatshown in FIG. 4. Such rotation causes the lever arms .11 to becomedisengaged from the locking pins 14 which, being urged by springs 27,pass through the apertures 32 and enter the recesses 33 in sides of thebolt 3 to maintain it in the extended position.

If an attempt is made to force the lock by drilling into the mechanism,the drill point will force the cup 9 inwardly against the action ofsprings 19. The lugs it) on the side of the cup 9 will in turn cause thelever arms 11 to be rotated out of engagement with the locking pins 14and, due to the biasing action of springs permits the pins 14 to snapinto the recesses 33 in the sides of the bolt 3 to maintain it in theextended position.

Another embodiment of the instant invention is shown in FIGS. 6-11. Inthis embodiment instead of the cup or shield 9 which surrounds only thetumbler mechanism of a combination lock, a liner or shield 38 which slipfits within the lock box 39 and encloses the entire mechanism isprovided. The open face of the liner 38 faces the rear of the lock box39. An opening 41 in the bottom Wall of the liner 38 is sufiicientlylarge to clear the collar 42 which supports the spindle 43 for thetumbler mechanism, shown generally at 44. This construction againpermits the tumblers to ride on the collar 42 without coming in contactwith the bot-tom of the liner 38 and consequently not restricting thefreedom of movement of the liner 33, which is essential for the properoperation of the device, which will be described in more detailhereinafter. The dial 45, shaft 46, lock box 39, spindle 43, tumblermechanism 4-4, bolt 40, and lever 47 which coacts with the tumblermechanism 44 to move the bolt 4% are as found in conventionalcombination lock structures, well known to those skilled in the art. Thelever 47 is rotatably mounted on the support shown generally at 50, orequiv.- alent structure, and urged into engagement with the tumblermechanism by spring 60.

The bolt 40, which is provided with recesses 48 in the sides thereofadjacent the inner end of the bolt 40, is supported for sliding movementin the slide 49. The inner liner 38 is interrupted at the bolt end ofthe lock box 39 to permit mounting of the slide 49, the front end ofwhich is secured by welding or other convenient means adjacent theopening for the bolt 40. The bolt 44) and slide 49 thus do not restrictthe movement of the liner 38 when it functions to prevent forcing thelock open. A U-shaped support 51, which is of greater width than theslide 49, is secured by riveting, welding or otherwise to the slide 49for support thereby. The upstanding portions 52 of the U-shaped member51 face the open side of the lock box 39. A threaded stud or nut andbolt arrangement 53 is located on each side of the bolt 4% and supportedin the intervening space between the upstanding portions 52 of theU-shaped member 51 and the upstanding portions 54 of the slide 49.Locking pins 55 located on each side of bolt 40 are also independentlysupported between the upstanding portions of the U-shaped support 51 andthe slide 49. The locking pins 55 are urged toward the bolt 40 bysprings 56 which are retained on the locking pins 55 by snap rings 57secured in circumferential grooves adjacent the innermost ends of thelocking pins 55. The upstanding portions of the slide 49 and theU-shaped support 51 are apertured as at 58 and 59, respectively, topermit free sliding movement of the locking pins 55 therethrough. Therecesses 48 in the bolt 4% are so located as to be in registry with theapertures 58 when the bolt 49 is in the extended position. The lockingpins 55 are restrained in a cocked position out of engagement with therecesses 48 in the bolt 40 by catches 61 which are mounted on the nutand bolt arrangement 53 for free rotation thereon. In the cockedposition of the locking pins 55 the independent catches 61 seat betweenthe snap rings 57 and the upstanding portions 54 of the slide 49. Thecatches 6-1 are urged to maintain the locking pins 55 in the cookedposition by springs 62 carried on the nut and bolt arrangement 53. Onearm 63 of each spring is in contact with a pin 64 on each catch 61 whichextends normally from the plane of the catch 61 toward the side walls ofthe lock box 39 a suflicient distance to contact a lever bar 65extending along each side wall of lock box 39. Each lever bar 65 has acrank arm 66 which is rotatably supported in the lock box end walls 67and is positioned to rest on a long edge 68 of the liner 38. The arm 63,pin 64 and lever bar 65 collectively comprise a restraining leverarrangement which maintains the liner 38 in a predetermined or fioating"position within the lock box relative to the tumbler mechanism.

The tension of all springs employed in this embodiment must be such asto prevent operation of the locking pins 55 under normal operation.

As in the previous embodiment, a flange 69 is rigidly secured to theedge of the liner 38 remote from the bolt 40. The flange 69 projectsover the rearmost element of the tumbler mechanism 44 for a purpose tobe hereinafter explained.

Again, in this embodiment if an attempt is made to force the lockmechanism by punching the tumblers, the punching force exerted willcause the tumbler mechanism to contact the flange 69 thereby moving theliner 38 in the direction of the open side. This motion of the liner 38is transmitted to the lever bars 65 which individually lift the pins 64thereby rotating the catches 61 out of engagement with the locking pins55 permitting the latter to enter the recesses 48 in the sides of thebolt 40 to maintain it in locked or extended position.

In the event an attempt is made to force the lock mechanism by drillinginto the lock box 39, the liner 38 will be moved in the direction of theopen side. This motion of the liner 38 again sets off the same operatingsequence of the lever bars 65, pins 64 and catches 61, to release thelocking pins 55 from the cocked position, as shown in FIG. 8, for entryinto the recesses 48 of the bolt 40, as shown in FIG. 9, to maintain thelatter in the locked or extended position.

Having thus described my invention, what I desire to claim and secure byLetters Patent is:

*1. In a combination lock including a lock box, a sliding bolt and atumbler mechanism for operating said bolt in response to predeterminedsettings of said tumbler mechanism, a pair of opposed spring biasedlocking pins mounted within said lock box for movement in a directionnormal to the direction of travel of said bolt, and recesses on saidbolt for receiving said locking pins, the improvement comprising ashield dimensionally greater than said tumbler mechanism interposedbetween said lock box and said tumbler mechanism, said shield includinga planar portion located between a wall of said lock box and saidtumbler mechanism and having a flange portion extending normal to saidplanar portion and surrounding said tumbler mechanism, guide meansincluding parallel spaced members defining a vertical slot attached tosaid lock box inwardly thereof and vertically aligned, spaced lugs onthe flange portion of said shield, one of said lugs received in saidslot orienting said shield relative to said tumbler mechanism, resilientmeans supported within said lock box and engaging said shield forexerting a force sutficient to maintain said shield in a predeterminedposition in said guide means relative to said tumbler mechanism, a latchengaging each of said locking pins to maintain it out of engagement wtihan adjacent one of said recesses, each latch including a projectionthereon coacting with said vertically aligned, spaced lugs abutmentmeans on said shield for displacement of said shield upon application ofa force to said tumbler mechanism in excess of the force exerted by saidresilient means, displacement of said shield vertically in said guidemeans moving each said projection in an arcuate path thereby releasingeach of said locking pins from the latch associated therewith forengagement with an adjacent recess to retain said bolt in a lockedposition.

2. In a combination lock including a lock box, a sliding bolt and atumbler mechanism for operating said bolt in response to predeterminedsettings of said tumbler mechanism, a spring biased locking pin mountedon each side of said bolt within said lock box for movement in adirection normal to the direction of travel of said bolt, and a recesson each side of said bolt for receiving an adjacent locking pin, theimprovement comprising a shield dimensionally greater than said tumblermechanism interposed between said lock box and said tumbler mechanism,said shield including a planar portion located between a wall of saidlock box and said tumbler mechanism and having a flange portionextending normal to said planar portion and surrounding said tumblermechanism, guide means including parallel spaced members defining avertical slot attached to said lock box inwardly thereof and verticallyaligned, spaced lugs on the flange portion of said shield, one of saidlugs received in said slot orienting said shield relative to saidtumbler mechanism, resilient means supported within said lock box andengaging said shield for exerting a force sufficient to maintain saidshield in a predetermined position in said guide means relative to saidtumbler mechanism, a latch engaging each said locking pin to maintain itout of engagement with the adjacent recess, a projection on each saidlatch extending through the opening between said vertically aligned,spaced lugs for slidable movement of said shield relative to said lockbox, abutment means on said shield coacting with said tumbler mechanismfor displacement of said shield upon application of a force to saidtumbler mechanism in excess of the force exerted by said resilientmeans, displacement of said shield vertically inwardly of said lock boxin said guide means moving each said projection in an arcuate paththereby releasing each said locking pin from the latch associatedtherewith for engagement with an adjacent recess to retain said bolt inlocked position.

3. In a combination lock including a lock box, a sliding bolt and amechanism for operating said bolt in response to predetermined settingsof said mechanism, a spring biased locking pin mounted on each side ofsaid bolt within said lock box for movement in a direction normal to thedirection of travel of said bolt, said bolt having a recess on each sidethereof for receiving an adjacent locking pin, the improvementcomprising a liner within said lock box and surrounding said mechanism,said liner mounted for independent relative motion to said mechanism, aspring biased latch engaging each said locking pin to maintain it out ofengagement with an adjacent recess, a lever bar on each side of saidlock box parallel to the direction of travel of said bolt and mountedwithin said lock box for arcuate travel in a direction normal to thelength of said liner, each said lever bar normally contacting an edge ofsaid lock box parallel to the direction of motion of said bolt, eachsaid latch including a projecting pin contacting an adjacent lever bar,abutment means on said liner coacting with said mechanism fordisplacement of said liner upon application of a force to said mechanismin excess of the force exerted by each said spring biased latch,displacement of said liner relative to said mechanism moving each saidlever bar and simultaneously acting on each said projecting pin to raisethe latch attached thereto out of engagement with the associated lockingpin permitting each said locking pin to engage an adjacent recess andretain said bolt in locked position.

4. In a combination lock including a lock box, a movable bolt, andtumbler mechanism for moving said bolt in accordance with predeterminedsettings of said tumbler mechanism and releasable locking means adaptedto engage said bolt :for retaining it in an extended position, theimprovement comprising a shield dimensionally greater than said tumblermechanism interposed between said lock box and said tumbler mechanism,said shield including a planar portion located between a wall of saidlock box and said tumbler mechanism and having a flange portionextending normal to said planar portion and surrounding said tumblermechanism, restraining lever means 3,077,099 7 communicating with saidflange portion of said shield maintaining said shield in a predeterminedposition within said lock box relative to said tumbler mechanism,pivotally mounted linkage means normally engaging and maintaining saidreleasable locking means out of engage- 5 ment with said bolt, limitingmeans carried by said shield 146,782 and coasting with said linkagemeans to trip said releas- 591,200 able locking means for engagementwith said bolt respon- 666,185 sive to displacement of said shield fromthe position 1,613,755

determined by said restraining lever means upon applica- 1;) 2,575,674

tion of a force to said shield in excess of the force exerted by saidretsraining lever means.

References Cited in the file of this patent UNITED STATES PATENTSRichardson Jan. 27, 1874 Stevenson Oct. 5, 1897 Damon Jan. 15, 1901Hunter Jan. 11, 1927 Miller Nov. 20, 1951

3. IN A COMBINATION LOCK INCLUDING A LOCK BOX, A SLIDING BOLT AND AMECHANISM FOR OPERATING SAID BOLT IN RESPONSE TO PREDETERMINED SETTINGSOF SAID MECHANISM, A SPRING BIASED LOCKING PIN MOUNTED ON EACH SIDE OFSAID BOLT WITHIN SAID LOCK BOX FOR MOVEMENT IN A DIRECTION NORMAL TO THEDIRECTION OF TRAVEL OF SAID BOLT, SAID BOLT HAVING A RECESS ON EACH SIDETHEREOF FOR RECEIVING AN ADJACENT LOCKING PIN, THE IMPROVEMENTCOMPRISING A LINER WITHIN SAID LOCK BOX AND SURROUNDING SAID MECHANISM,SAID LINER MOUNTED FOR INDEPENDENT RELATIVE MOTION TO SAID MECHANISM, ASPRING BIASED LATCH ENGAGING EACH SAID LOCKING PIN TO MAINTAIN IT OUT OFENGAGEMENT WITH AN ADJACENT RECESS, A LEVER BAR ON EACH SIDE OF SAIDLOCK BOX PARALLEL TO THE DIRECTION OF TRAVEL OF SAID BOLT AND MOUNTEDWITHIN SAID LOCK BOX FOR ARCUATE TRAVEL IN A DIRECTION NORMAL TO THELENGTH OF SAID LINER, EACH SAID LEVER BAR NORMALLY CONTACTING AN EDGE OFSAID LOCK BOX PARALLEL TO THE DIRECTION OF MOTION OF SAID BOLT, EACHSAID LATCH INCLUDING A PROJECTING PIN CONTACTING AN ADJACENT LEVER BAR,ABUTMENT MEANS ON SAID LINER COACTING WITH SAID MECHANISM FORDISPLACEMENT OF SAID LINER UPON APPLICATION OF A FORCE TO SAID MECHANISMIN EXCESS OF THE FORCE EXERTED BY EACH SAID SPRING BIASED LATCH,DISPLACEMENT OF SAID LINER RELATIVE TO SAID MECHANISM MOVING EACH SAIDLEVER BAR AND SIMULTANEOUSLY ACTING ON EACH SAID PROJECTING PIN TO RAISETHE LATCH ATTACHED THERETO OUT OF ENGAGEMENT WITH THE ASSOCIATED LOCKINGPIN PERMITTING EACH SAID LOCKING PIN TO ENGAGE AN ADJACENT RECESS ANDRETAIN SAID BOLT IN LOCKED POSITION.